Movement disorder symptom control

Abstract

The disclosure describes a method and system or controlling symptoms of patients suffering from Parkinson's Disease. In some examples, one or more biomarkers indicative of a patient's present symptoms are determined. The biomarkers may be used to control therapy delivered to the patient in a closed-loop manner. In addition, biomarkers may be used as an indication of therapy effectiveness.

What is claimed is: 
     
       1. A method comprising:
 acquiring, with a medical device, one or more electrical signals from a brain of a patient being treated for a movement disorder with a medication and electrical stimulation; 
 determining whether at least a first predetermined biomarker is present in a subthalamic nucleus (STN) electrical signal of the one or more electrical signals, the first predetermined biomarker associated with at least one of the patient being under-treated or the presence of movement disorder symptoms, the first predetermined biomarker comprising a low beta band peak in the STN electrical signal; 
 determining whether at least a second predetermined biomarker is present in the STN electrical signal or a motor cortex electrical signal of the one or more electrical signals, the second predetermined biomarker associated with at least one of the patient being over-treated or the presence of side effects of the medication, the second predetermined biomarker comprising one or more of a gamma band peak in the STN electrical signal, a gamma band peak in the motor cortex electrical signal, and a low beta band peak in the motor cortex electrical signal; and 
 adjusting, based on whether the first predetermined biomarker is present or whether the second predetermined biomarker is present, at least one parameter of the electrical stimulation to maintain the patient within a therapeutic window, wherein adjusting the at least one parameter comprises one or more of:
 based on the first predetermined biomarker being present, one or more of:
 applying the electrical stimulation with a frequency between approximately 55 and 65 Hz; 
 applying the electrical stimulation with a frequency between approximately 120 and 140 Hz; or 
 applying the electrical stimulation with a frequency alternating between approximately 55 and 65 Hz and approximately 120 and 140 Hz; 
 
 based on the gamma band peak being present in the STN electrical signal, applying bursts of the electrical stimulation with a frequency of approximately the gamma band peak in the STN electrical signal; 
 based on the gamma band peak being present in the motor cortex electrical signal, applying bursts of the electrical stimulation with a frequency approximately of the gamma band peak in the motor cortex electrical signal; 
 based on the low beta band peak being present in the motor cortex electrical signal, applying the electrical stimulation with a frequency between approximately 55 and 65 Hz; or 
 based on the second predetermined biomarker being present, applying the electrical stimulation with a frequency alternating between approximately 55 and 65 Hz and approximately 120 and 140 Hz. 
 
 
     
     
       2. The method of  claim 1 , further comprising delivering the electrical simulation to a subthalamic nucleus (STN) of the brain of the patient. 
     
     
       3. The method of  claim 1 , further comprising:
 acquiring an updated electrical signal from the STN; 
 acquiring an updated electrical signal from the motor cortex; 
 determining whether at least the first predetermined biomarker is present in the updated electrical signal from the STN; 
 determining whether at least the second predetermined biomarker is present in the updated electrical signal from the STN or the updated electrical signal from the motor cortex; 
 analyzing the efficacy of the adjusted parameter of the electrical stimulation based on whether the first predetermined biomarker is present in the updated electrical signal from the STN or the second predetermined biomarker is present in the updated electrical signal from the STN or the updated electrical signal from the motor cortex; and 
 readjusting the adjusted parameter of the electrical stimulation based on the efficacy of the adjusted parameter of the electrical stimulation. 
 
     
     
       4. The method of  claim 1 , wherein the first predetermined biomarker and the second predetermined biomarker are patient specific. 
     
     
       5. The method of  claim 4 , further comprising:
 determining, based on whether the second predetermined biomarker is present, a patient state, 
 wherein the patient state is dyskinesia. 
 
     
     
       6. The method of  claim 1 , wherein the first predetermined biomarker and the second predetermined biomarker are specific to the movement disorder. 
     
     
       7. The method of  claim 6 , wherein the movement disorder is Parkinson's disease. 
     
     
       8. A system comprising:
 an implantable medical device comprising a memory and a processor; 
 a first electrode in communication with the implantable medical device, the first electrode configured to acquire one or more electrical signals from a subthalamic nucleus (STN) of a brain of a patient being treated for a movement disorder with a medication and electrical stimulation; 
 a second electrode in communication with the implantable medical device, the second electrode configured to acquire one or more electrical signals from a motor cortex of the brain of the patient; 
 wherein the processor is configured to:
 determine whether at least a first predetermined biomarker is present in the one or more electrical signals acquired from the STN, the first predetermined biomarker associated with at least one of the patient being under-treated or the presence of movement disorder symptoms, the first predetermined biomarker comprising a low beta band peak in the electrical signals acquired from the STN; 
 determine whether at least a second predetermined biomarker is present in the one or more electrical signals acquired from the STN or the motor cortex, the second predetermined biomarker associated with at least one of the patient being over-treated or the presence of side effects of the medication, the second predetermined biomarker comprising one or more of a gamma band peak in the electrical signals acquired from the STN, a gamma band peak in the electrical signals acquired from the motor cortex, and a low beta band peak in the electrical signals acquired from the motor cortex; and 
 
 adjust, based on whether or not the first predetermined biomarker is present and whether or not the second predetermined biomarker is present, at least one parameter of the electrical stimulation to maintain the patient within a therapeutic window, wherein to adjust the at least one parameter, the processor is configured to:
 based on the first predetermined biomarker being present, one or more of:
 apply the electrical stimulation with a frequency between approximately 55 and 65 Hz; 
 apply the electrical stimulation with a frequency between approximately 120 and 140 Hz; or 
 apply the electrical stimulation with a frequency alternating between approximately 55 and 65 Hz and approximately 120 and 140 Hz; 
 
 based on the gamma band peak being present in the STN electrical signal, apply bursts of the electrical stimulation with a frequency of approximately the gamma band peak in the STN electrical signal; 
 based on the gamma band peak being present in the motor cortex electrical signal, apply bursts of the electrical stimulation with a frequency approximately of the gamma band peak in the motor cortex electrical signal; 
 based on the low beta band peak being present in the motor cortex electrical signal, apply the electrical stimulation with a frequency between approximately 55 and 65 Hz; or 
 based on the second predetermined biomarker being present, apply the electrical stimulation with a frequency alternating between approximately 55 and 65 Hz and approximately 120 and 140 Hz. 
 
 
     
     
       9. The system of  claim 8 , wherein the stimulation generator is configured to deliver electrical stimulation to a subthalamic nucleus (STN) of the brain of the patient via the first electrode. 
     
     
       10. The system of  claim 8 , wherein the first electrode is further configured to acquire an updated first electrical signal from the STN; the second electrode is further configured to acquire an updated second electrical signal from the motor cortex; and
 wherein the processor is further configured to:
 determine whether at least the first predetermined biomarker is present in the updated first electrical signal; 
 determine whether at least the second predetermined biomarker is present in the updated first electrical signal or the updated second electrical signal; 
 analyze the efficacy of the adjusted parameter of the electrical stimulation based on whether the first predetermined biomarker is present in the updated first electrical signal or whether the second predetermined biomarker is present in the updated first electrical signal or the updated second electrical signal; and 
 readjust the adjusted parameter of the electrical stimulation based on the efficacy of the adjusted parameter of the electrical stimulation. 
 
 
     
     
       11. The system of  claim 8 , wherein the first predetermined biomarker and the second predetermined biomarker are patient specific. 
     
     
       12. The system of  claim 11 , wherein the processor is further configured to:
 determine, based on whether the second predetermined biomarker is present, a patient state, 
 wherein the patient state is dyskinesia. 
 
     
     
       13. The system of  claim 8 , wherein the first predetermined biomarker and the second predetermined biomarker are specific to the movement disorder. 
     
     
       14. The system of  claim 13 , wherein the movement disorder is Parkinson's disease.